Close range photography, such as where the subject to be photographed is between 2 and 18 inches from the camera, is presently being used in various diverse applications; for example, such photography finds wide use in various medical, passport, dental, journalistic and law enforcement applications, as well as for pleasure by naturalists and amateur photographers. Close range photography presents problems which are not common to photography in general. For example, positioning of the subject and selection of a proper focal distance for the lens is necessarily a more exacting procedure requiring greater care in close-up photography than in ordinary photographic applications. Prior solutions for such problems are taught in Lester A. Dine et al U.S. Pat. Nos. 3,687,030 (granted Aug. 29, 1972) and 3,836,927 (granted Sept. 17, 1974).
The use of a flash-type light source for close-up photography presents an additional problem in that, as the distance between the camera lens and the subject is varied, the intensity of the light from the camera flash incident on the subject correspondingly varies, since the light incident on a subject at a maximum close range distance (18 inches, for example) from the camera lens is substantially less than if the same subject were positioned at a minimum close range (2 inches, for example) for the same amount of light emanating from the flash source. One solution to this problem has been set forth in the above-mentioned U.S. Pat. No. 3,836,927 which provides means for adjusting the illumination depending upon distance.
Currently, cameras are also available which satisfy this need by sensing the amount of light falling on the subject, and automatically turning off the flash when the predetermined required amount of light has illuminated the subject. However, in cameras in common use, the source of flash is within the same housing as the camera itself, and is necessarily offset to some extent from the lens. This results in a parallax effect that causes the light emitted from the flash in very close-up situations to be non-uniform over the subject in the area of view of the lens.
Accordingly, one object of the present invention is to provide a new and improved close-up camera which utilizes current conventional cameras, modified to overcome these disadvantages and to provide the benefits of uniform illumination over the field of view, to provide proper illumination of the subject at various close range distances from the camera lens to provide proper illumination of the subject.
Still another object of the present invention is to provide such an improved camera in association with simple attachments to facilitate proper focusing and framing of close range subjects.
It is still another object of the present invention to provide such an improved close-up camera by simple and economic modifications of a conventional camera.